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Low noise,continuous-wave single-frequency 1.5-μm laser generated by a singly resonant optical parametric oscillator 被引量:3
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作者 刘建丽 刘勤 +2 位作者 李宏 李鹏 张宽收 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第11期312-316,共5页
We report a low noise continuous-wave (CW) single-frequency 1.5-μm laser source obtained by a singly resonant optical parametric oscillator (SRO) based on periodically poled lithium niobate (PPLN). The SRO was ... We report a low noise continuous-wave (CW) single-frequency 1.5-μm laser source obtained by a singly resonant optical parametric oscillator (SRO) based on periodically poled lithium niobate (PPLN). The SRO was pumped by a CW single-frequency Nd:YVO4 laser at 1.06μm. The 1.02 W of CW single-frequency signal laser at 1.5 μm was obtained at pump power of 6 W. At the output power of around 0.75 W, the power stability was better than ±l.5% and no mode-hopping was observed in 30 min and frequency stability was better than 8.5 MHz in 1 min. The signal wavelength could be tuned from 1.57 to 1.59 μm by varying the PPLN temperature. The 1.5-μm laser exhibits low noise characteristics, the intensity noise of the laser reaches the shot noise limit (SNL) at an analysis frequency of 4 MHz and the phase noise is less than 1 dB above the SNL at analysis frequencies above 10 MHz. 展开更多
关键词 singly resonant optical parametric oscillator 1.5-μm laser single-frequency operation low noise
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Residual Phase Noise and Time Jitters of Single-Chip Digital Frequency Dividers
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作者 Lu-Lu Yan Sen Meng +3 位作者 Wen-Yu Zhao Wen-Ge Guo Hai-Feng Jiang Shou-Gang Zhang 《Journal of Electronic Science and Technology》 CAS CSCD 2015年第3期264-268,共5页
In this paper, we demonstrate the residual phase noise of a few microwave frequency dividers which usually limit the performance of frequency synthesizers. In order to compare these dividers under different operation ... In this paper, we demonstrate the residual phase noise of a few microwave frequency dividers which usually limit the performance of frequency synthesizers. In order to compare these dividers under different operation frequencies, we calculate additional time jitters of these dividers by using the measured phase noise. The time jitters are various from -0.1 fs to 43 fs in a bandwidth from 1 Hz to 100 Hz in dependent of models and operation frequencies. The HMC series frequency dividers exhibit outstanding performance for high operation frequencies, and the time jitters can be sub-fs. The time jitters of SP8401, MC10EP139, and MC100LVEL34 are comparable or even below that of HMC series for low operation frequencies. 展开更多
关键词 frequency divider phase noise spectra analysis time jitter
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CMOS Direct-Injection Divide-by-3 Injection-Locked Frequency Dividers
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作者 Chia-Wei Chang Jhin-Fang Huang +2 位作者 Sheng-Lyang Jang Ying-Hsiang Liao Miin-Horng Juang 《Journal of Measurement Science and Instrumentation》 CAS 2010年第S1期118-120,128,共4页
This paper proposes CMOS LC-tank divide-by-3 injection locked frequency dividers(ILFDs)fabricated in 0.18μn and 90nm CMOS process and describes the circuit design,operation principle and measurement results of the IL... This paper proposes CMOS LC-tank divide-by-3 injection locked frequency dividers(ILFDs)fabricated in 0.18μn and 90nm CMOS process and describes the circuit design,operation principle and measurement results of the ILFDs.The ILFDs use two injection series-MOSFETs across the LC resonator and a differential injection signal is applied to the gates of injection MOSFETs.The direct-injection divide-by-3 ILFDs are potential for radio-frequency application and can have wide locking range. 展开更多
关键词 LC-tank divide-by-3 injection-locked frequency divider DIRECT-INJECTION locking range CMOS
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A Programmable 2.4GHz CMOS Multi-Modulus Frequency Divider 被引量:1
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作者 李志强 陈立强 +1 位作者 张健 张海英 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第2期224-228,共5页
A programmable multi-modulus frequency divider is designed and implemented in a 0. 35μm CMOS process. The multi-modulus frequency divider is a single chip with two dividers in series,which are divided by 4 or 5 presc... A programmable multi-modulus frequency divider is designed and implemented in a 0. 35μm CMOS process. The multi-modulus frequency divider is a single chip with two dividers in series,which are divided by 4 or 5 prescaler and by 128-255 multi-modulus frequency divider. In the circuit design, power and speed trade-offs are analyzed for the prescaler, and power optimization techniques are used according to the input frequency of each divider cell for the 128-255 multimodulus frequency divider. The chip is designed with ESD protected I/O PAD. The dividers chain can work as high as 2.4GHz with a single ended input signal and beyond 2.6GHz with differential input signals. The dual-modulus prescaler consumes 11mA of current while the 128-255 multi-modulus frequency divider consumes 17mA of current with a 3.3V power supply. The core area of the die without PAD is 0.65mm × 0.3mm. This programmable multi-modulus frequency divider can be used for 2.4GHz ISM band PLL-based frequency synthesizers. To our knowledge, this is the first reported multi-modulus frequency divider with this structure in China. 展开更多
关键词 PRESCALER frequency divider PROGRAMMABLE multi-modulus frequency synthesizer
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Design of Down Scalers in Mixed-Signal GHz Frequency Synthesizer 被引量:1
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作者 徐勇 王志功 +3 位作者 仇应华 李智群 胡庆生 闵锐 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第9期1711-1715,共5页
An optimized method is presented to design the down scalers in a GHz frequency synthesizer. The down scalers are comprised of dual modulus prescaler (DMP) and programmable & pulse swallow divider,different methods ... An optimized method is presented to design the down scalers in a GHz frequency synthesizer. The down scalers are comprised of dual modulus prescaler (DMP) and programmable & pulse swallow divider,different methods of high frequency analog circuit and digital logical synthesis are adopted respectively. Using a DMP high speed, lower jitter and lower power dissipation are obtained,and output frequency of 133.0MHz of the DMP working at divide-by-8 shows an RMS jitter less than 2ps. The flexibility and reusability of the progrs, mmable divider is high;its use could be extended to many complicated frequency synthesizers. By comparison,it is a better design on performance of high-frequency circuit and good design flexibility. 展开更多
关键词 PLL frequency synthesizer dual-modulus prescaler PROGRAMMABLE pulse swallow divider
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Key technologies of frequency-hopping frequency synthesizer for Bluetooth RF front-end
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作者 徐勇 王志功 +3 位作者 李智群 章丽 闵锐 徐光辉 《Journal of Southeast University(English Edition)》 EI CAS 2005年第3期260-262,共3页
A scheme of a frequency-hopping frequency-synthesizer applied to a Bluetooth ratio frequency (RF) front-end is presented,and design of a voltage controlled oscillator (VCO) and dual-modulus prescaler are focused o... A scheme of a frequency-hopping frequency-synthesizer applied to a Bluetooth ratio frequency (RF) front-end is presented,and design of a voltage controlled oscillator (VCO) and dual-modulus prescaler are focused on.It is fabricated in a 0.18 μm mixed-signal CMOS (complementary metal-oxide-semiconductor transistor) process.The power dissipation of VCO is low and a stable performance is gained.The measured phase noise of VCO at 2.4 GHz is less than -114.32 dBc/Hz.The structure of the DMP is optimized and a novel D-latch integrated with "OR" logic gate is used.The measured results show that the chip can work well under a 1.8 V power supply.The power dissipation of the core part in a dual modulus prescaler is only 5.76 mW.An RMS jitter of 2 ps is measured on the output signal at 118.3 MHz.It is less than 0.02% of the clock period. 展开更多
关键词 BLUETOOTH frequency hopping frequency synthesizer voltage controlled oscillator (VCO) dualmodulus prescaler programmable divider
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Frequency synthesizer for DRM/DAB/AM/FM RF front-end
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作者 雷雪梅 王志功 +1 位作者 王科平 沈连丰 《Journal of Southeast University(English Edition)》 EI CAS 2013年第3期242-246,共5页
This paper describes a wideband low phase noise frequency synthesizer.It operates in the multi-band including digital radio mondiale DRM digital audio broadcasting DAB amplitude modulation AM and frequency modulation ... This paper describes a wideband low phase noise frequency synthesizer.It operates in the multi-band including digital radio mondiale DRM digital audio broadcasting DAB amplitude modulation AM and frequency modulation FM .In order to cover the signals of the overall frequencies a novel frequency planning and a new structure are proposed. A wide-band low-phase-noise low-power voltage-control oscillator VCO and a high speed wide band high frequency division ratio pulse swallow frequency divider with a low power consumption are presented.The monolithic DRM/DAB/AM/FM frequency synthesizer chip is also fabricated in a SMIC's 0.18-μm CMOS process.The die area is 1 425 μm ×795 μm including the test buffer and pads. The measured results show that the VCO operating frequency range is from 2.22 to 3.57 GHz the measured phase noise of the VCO is 120.22 dBc/Hz at 1 MHz offset the pulse swallow frequency divider operation frequency is from 0.9 to 3.4 GHz.The phase noise in the phase-locked loop PLL is-59.52 dBc/Hz at 10 kHz offset and fits for the demand of the DRM/DAB/AM/FM RF front-end. The proposed frequency synthesizer consumes 47 mW including test buffer under a 1.8 V supply. 展开更多
关键词 frequency synthesizer wideband voltage-controloscillator pulse swallow frequency divider low phase noise
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0.18μm CMOS programmable frequency divider design for DVB-T
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作者 胡庆生 仲建锋 何小虎 《Journal of Southeast University(English Edition)》 EI CAS 2008年第2期159-162,共4页
The implementation of a programmable frequency divider, which is one of the components of the phase-locked loop (PLL) frequency synthesizer for digital video broadcastingterrestrial (DVB-T) and other modem communi... The implementation of a programmable frequency divider, which is one of the components of the phase-locked loop (PLL) frequency synthesizer for digital video broadcastingterrestrial (DVB-T) and other modem communication systems, is presented. By cooperating with a dual-modulus prescaler, this divider can realize an integer frequency division from 926 to 1 387. Besides the traditional standard cell design flow, such as logic synthesis, placement and routing, the interactions between front-end and back-end are also considered to optimize the design flow under deep submicron technology. By back-annotating the back-end information to front-end design, a custom wire-load model is created which is more practical compared with the default model. This divider has been fabricated in TSMC 0. 18μm CMOS technology using Artisan standard cell library. The chip area is 675 μm × 475 μm and the power consumption is about 2 mW under a 1.8 V power supply. Measurement results show that it works correctly and can realize a frequency division with high precision. 展开更多
关键词 programmable frequency divider frequency synthesizer standard cell DVB-T
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基于频率加权能量算子与1.5维谱结合的发电机特征振动信号增强 被引量:3
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作者 何玉灵 孙凯 +1 位作者 王涛 白洁 《大电机技术》 2021年第1期64-70,共7页
针对多极发电机故障振动信号信噪比低,故障识别难度高的不足,本文提出了频率加权能量算子(FWEO)与1.5维谱结合的方法来对发电机振动信号进行特征增强和滤噪。该方法应用频率加权能量算子来提取瞬态冲击特征和滤噪,应用1.5维谱来进行信... 针对多极发电机故障振动信号信噪比低,故障识别难度高的不足,本文提出了频率加权能量算子(FWEO)与1.5维谱结合的方法来对发电机振动信号进行特征增强和滤噪。该方法应用频率加权能量算子来提取瞬态冲击特征和滤噪,应用1.5维谱来进行信号的二次特征增强和抑噪。对3对极发电机定子匝间短路故障前后定子振动数据的处理效果表明,本文所提方法能有效对发电机特征振动信号进行增强并实现有效滤噪,实现故障的快速识别;其处理效果不仅优于单一的频率加权能量算子和单一的1.5维谱,而且与当前流行的最大相关峭度解卷积算法相比具有一定优越性。 展开更多
关键词 多对极发电机 定子匝间短路 振动信号 频率加权能量算子(FWEO) 1.5维谱
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An 8.5GHz 1∶8 Frequency Divider in 0.35μm CMOS Technology 被引量:4
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作者 陆建华 王志功 +5 位作者 田磊 陈海涛 谢婷婷 陈志恒 董毅 谢世钟 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2003年第4期366-369,共4页
An 1∶8 frequency divider is designed and realized in a 0 35μm standard CMOS technology.The chip consists of three stages of 1∶2 divider cells,which are constructed with source couple logic (SCL) flip flops.By rev... An 1∶8 frequency divider is designed and realized in a 0 35μm standard CMOS technology.The chip consists of three stages of 1∶2 divider cells,which are constructed with source couple logic (SCL) flip flops.By revising the traditional topology of SCL flip flop,a divider with better performances is got.The results of measurement show that the whole chip achieves the frequency division at more than 8 5GHz.Each 1∶2 divider consumes about 11mW from a 3 3V supply.The divider can be used in RF and optic fiber transceivers and other high speed systems. 展开更多
关键词 frequency divider flip flop CMOS IC
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基于1.5维谱活跃频率的行星齿轮箱磨损故障诊断研究 被引量:1
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作者 毕浩程 蒋章雷 +2 位作者 李宇恒 吴国新 王红军 《机电工程》 CAS 北大核心 2021年第10期1305-1310,共6页
行星齿轮箱中多种频率成分相互耦合导致无法提取故障特征,针对这一问题,提出了基于1.5维谱(三阶累积量一维对角切片谱)活跃频率的行星齿轮箱磨损故障诊断的方法。该方法先将1.5维谱能够识别的二次相位耦合推广到符合实际意义的二次频率... 行星齿轮箱中多种频率成分相互耦合导致无法提取故障特征,针对这一问题,提出了基于1.5维谱(三阶累积量一维对角切片谱)活跃频率的行星齿轮箱磨损故障诊断的方法。该方法先将1.5维谱能够识别的二次相位耦合推广到符合实际意义的二次频率耦合,再将解耦出的参与耦合频率与耦合产生频率逐点相乘,以得到其活跃频率;然后通过观察活跃频率与故障频率之间的关系,判断行星齿轮箱是否发生故障;实验部分首先运用该方法从仿真信号中提取出了活跃频率,然后通过搭建行星齿轮箱齿面磨损故障实验台采集振动信号,最后运用该方法提取出了其磨损故障特征频率。研究结果表明:传统的傅里叶变换方法不能提取出故障特征频率,基于1.5维谱活跃频率的磨损故障诊断方法能够从行星齿轮箱振动信号中提取出故障特征频率,实现了对行星齿轮箱磨损故障的诊断,对行星齿轮箱磨损故障诊断具有重要意义。 展开更多
关键词 行星齿轮箱 故障诊断 1.5维谱 活跃频率 频率耦合
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最优共振带提取与1.5维谱的滚动轴承早期故障诊断方法 被引量:2
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作者 郭俊 黄慧杰 +1 位作者 王新 王洪波 《机械设计与制造》 北大核心 2019年第5期178-181,共4页
滚动轴承的振动信号反映到频谱图中,会出现共振带,能够有效并准确提取共振带加以分析是滚动轴承故障诊断常用方法。为了准确提取出共振带,采用巴特沃斯带通滤波器对共振频带进行提取,为了得到最优共振带,将采用特征频率强度系数这一指... 滚动轴承的振动信号反映到频谱图中,会出现共振带,能够有效并准确提取共振带加以分析是滚动轴承故障诊断常用方法。为了准确提取出共振带,采用巴特沃斯带通滤波器对共振频带进行提取,为了得到最优共振带,将采用特征频率强度系数这一指标来反映提取的共振带效果,然后利用具有高强降噪特性的1.5维谱来对滤波信号进行特征提取.通过仿真信号以及试验信号对该方法进行验证,结果表明,该方法能够在强噪背景下对特征的提取以及实现滚动轴承早期故障诊断。 展开更多
关键词 滚动轴承 早期故障 共振带 特征频率强度系数 1.5维谱
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燃气轮机1.5级轴流压气机气动噪声预测 被引量:1
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作者 卢华兵 王正祥 +2 位作者 刘威 肖友洪 刘志刚 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2023年第3期379-385,共7页
针对多排叶片旋转机械气动声源的复杂性,本文研究了一种预测多排叶轮气动噪声的数值模拟方法。基于混合计算方法研究了燃气轮机1.5级压气机的气动噪声特性,采用剪切应力传输湍流模型对1.5级轴流压气机的三维非定常流场进行全通道计算并... 针对多排叶片旋转机械气动声源的复杂性,本文研究了一种预测多排叶轮气动噪声的数值模拟方法。基于混合计算方法研究了燃气轮机1.5级压气机的气动噪声特性,采用剪切应力传输湍流模型对1.5级轴流压气机的三维非定常流场进行全通道计算并获得声源,基于变分形式的Lighthill声类比耦合声源信息预测了压气机噪声,并在压气机动态实验台开展了流场和噪声实验研究。结果表明:非定常压力脉动傅里叶变换后峰值主要出现在叶片通过频率及其谐波处,且压力幅值随着叶频阶数的升高而降低;前传噪声有明显的声学指向性,具有明显的偶极子特征,离散噪声包含可传播的高阶模态;数值仿真的结果与实验吻合较好,本文研究的数值计算方法对多排叶轮的气动噪声预测具有较高的精度。 展开更多
关键词 1.5级压气机 气动噪声 叶片通过频率 数值模拟 声类比理论 声学噪声 指向性 频域分析 声辐射
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Design of a Frequency Divider with Reduced Complexity Based on a Resonant Tunneling Diode
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作者 杜睿 戴杨 杨富华 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第7期1292-1297,共6页
A novel edge-triggered D-flip-flop based on a resonant tunneling diode (RTD) is proposed and used to construct a binary frequency divider. The design is discussed in detail and the performance of the circuit is veri... A novel edge-triggered D-flip-flop based on a resonant tunneling diode (RTD) is proposed and used to construct a binary frequency divider. The design is discussed in detail and the performance of the circuit is verified using SPICE. Relying on the nonlinear characteristics of RTD,we reduced the number of components used in our DFF circuit to only half of that required using conventional CMOS SCFL technology. 展开更多
关键词 frequency divider D-flip-flop RTD reduced complexity
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A Low Power,High Sensitivity SiGe HBT Static Frequency Divider up to 90 GHz for Millimeter-Wave Application 被引量:2
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作者 Peigen Zhou Jixin Chen +2 位作者 Pinpin Yan Debin Hou Wei Hong 《China Communications》 SCIE CSCD 2019年第2期85-94,共10页
A layout and connection optimization for static frequency divider is presented. The layout optimization provides a new circle topology transistors placement and reasonable connection structure, which reduces the paras... A layout and connection optimization for static frequency divider is presented. The layout optimization provides a new circle topology transistors placement and reasonable connection structure, which reduces the parasitic effectively and enables self-oscillation frequency enhancement. Besides, bandwidth enhancement techniques based on a center-tap capacitor in input balun design and inductive peaking in latch design are adopted to improve further high frequency performance with low power consumption. As a proof of concept, design of a divide-by-2 static frequency divider in 0.13 μm SiGe BiCMOS technology is reported. With single-ended input clock signal, the divider is measured to be operated from 40 to 90 GHz. Phase noise measurements of a 90 GHz input clock signal indicate ideal behavior with no measurable noise contribution from the divider. The divider followed by a buffer that can deliver more than-10 dBm output power, which is sufficient to drive succeeding stage. To the author's knowledge, the divider exhibits a competitive power dissipation and the highest FOM among silicon based frequency dividers that operating higher than 70 GHz. 展开更多
关键词 E-band layout optimization MILLIMETER wave integrated circuits STATIC frequency DIVIDER SIGE
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Design of 0.18 μm CMOS programmable frequency divider based on standard cells
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作者 何小虎 胡庆生 《Journal of Southeast University(English Edition)》 EI CAS 2007年第1期31-34,共4页
The design of a programmable frequency divider, which is one of the components of the phase-locked loop (PLL) frequency synthesizer for transmitter and receiver in IEEE 802. 11 a standard, is investigated. The main ... The design of a programmable frequency divider, which is one of the components of the phase-locked loop (PLL) frequency synthesizer for transmitter and receiver in IEEE 802. 11 a standard, is investigated. The main steps in very large-scale integration (VLSI) design flow such as logic synthesis, floorplan and placement & routing (P & R) are introduced. By back-annotating the back-end information to the front-end design, the custom wire-load model is created and used for optimizing the design flow under deep submicron technology. The programmable frequency divider is implemented based on Artisan TSMC (Taiwan Semicoductor Manufacturing Co. Ltd. )0. 18μm CMOS (complementary metal-oxide-semiconductor) standard cells and fabricated. The Chip area is 1 360. 5μm^2 and can work in the range of 100 to 200 MHz. The measurement results indicate that the design conforms to the frequency division precision. 展开更多
关键词 programmable frequency divider frequency synthesizer standard cells CMOS
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基于频率耦合的1.5维能量谱的轴承故障诊断方法
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作者 梁好 蒋章雷 +1 位作者 李宇恒 徐小力 《组合机床与自动化加工技术》 北大核心 2020年第6期10-13,共4页
针对滚动轴承由于振动传递路径复杂以及强背景噪声而导致早期故障特征难以提取的问题,提出了基于频率耦合的1.5维能量谱的故障特征提取方法。用公式推导验证了1.5维谱不需要同时满足相位与频率耦合,能在只满足二次频率耦合的情况下使用... 针对滚动轴承由于振动传递路径复杂以及强背景噪声而导致早期故障特征难以提取的问题,提出了基于频率耦合的1.5维能量谱的故障特征提取方法。用公式推导验证了1.5维谱不需要同时满足相位与频率耦合,能在只满足二次频率耦合的情况下使用,这对实际信号直接进行1.5维谱分析有很大的帮助。该方法是在信号经过预处理后对信号进行对称差分能量算子解调,获得解调信号,再对解调信号进行1.5维谱分析,最后获得1.5维能量谱。通过对实验数据的分析,验证了1.5维能量谱在滚动轴承故障诊断中的有效性。 展开更多
关键词 1.5维能量谱 频率耦合 轴承故障诊断
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A fractional frequency divider based on phase switching and negative feedback delta-sigma modulator for MMMS applications 被引量:1
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作者 Liao Yilong Fan Xiangning +2 位作者 Lin Zhi Shi Yongjian Hua Zaijun 《High Technology Letters》 EI CAS 2019年第3期231-238,共8页
A fractional frequency divider based on phase switching and negative feedback delta-sigma modulator(NF-DSM) is presented. The phase switching circuit, realized by switching 8 signals generated by a divider-by-4 circui... A fractional frequency divider based on phase switching and negative feedback delta-sigma modulator(NF-DSM) is presented. The phase switching circuit, realized by switching 8 signals generated by a divider-by-4 circuit, is adopted to reduce the frequency division step. The NF-DSM, which can obtain smooth output spectra, is proposed to generate the fractional part of the division ratio, moreover, the integer part of the division ratio is realized by a divider-by-2/3 circuit chain. Fabricated in TSMC 0.18 μm RF CMOS technology, the fractional frequency divider achieves a measured operation frequency from 0.5 GHz to 8 GHz. With a 1.8 V supply voltage, the maximum current consumption of the whole divider is 17.5 mA, and the chip area is 0.58 mm^2, including the pads. 展开更多
关键词 delta-sigma modulator(DSM) divider-by-2/3 frequency divider phase switching
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采用1.5 t中频炉浇注4.4 t灰铸铁件的生产方法 被引量:1
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作者 吴军 张有功 孙涛 《现代铸铁》 CAS 2019年第6期16-19,共4页
介绍了采用1.5 t中频炉浇注4.4 t灰铸铁件的生产方法,详细阐述了化学成分、熔炼、分包以及温度控制情况,得出以下结论:(1)与6 t中频炉相比,采用1.5 t中频炉浇注铁液,每件铸件节约电费2500元左右;(2)浇注温度为1273~1307℃,铁液流动好,... 介绍了采用1.5 t中频炉浇注4.4 t灰铸铁件的生产方法,详细阐述了化学成分、熔炼、分包以及温度控制情况,得出以下结论:(1)与6 t中频炉相比,采用1.5 t中频炉浇注铁液,每件铸件节约电费2500元左右;(2)浇注温度为1273~1307℃,铁液流动好,铸件采用无冒口工艺,利用灰铸铁石墨化膨胀的补缩作用,生产的铸件无缩孔、气孔缺陷;(3)将第1炉w(C)量控制在3.3%~3.4%,w(Si)量控制在2.0%~2.1%,其余2炉化学成分按照控制范围的上限控制,可减少化学元素的烧损。 展开更多
关键词 灰铸铁 1.5 t中频炉 分炉熔炼
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A 30GHz Wideband CMOS Injection-Locked Frequency Divider for 60GHz Transceiver
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作者 Chunqi Shi Runxi Zhang Zongsheng Lai 《Communications and Network》 2013年第3期6-10,共5页
In this paper, a 30 GHz wide locking-range (26.2 GHz-35.7 GHz) direct injection-locked frequency divider (ILFD), which operating in the millimeter-wave (MMW) band, is presented. The locking range of the ILFD is extend... In this paper, a 30 GHz wide locking-range (26.2 GHz-35.7 GHz) direct injection-locked frequency divider (ILFD), which operating in the millimeter-wave (MMW) band, is presented. The locking range of the ILFD is extended by using differential injection topology. Besides, varactors are used in RLC resonant tank for extending the frequency tuning range. The post simulation results show that a wide locking-range of 9.5 GHz (30.7%) is achieved. When the VCO output frequency varies from 26.85 GHz to 34.42 GHz, the proposed ILFD can achieve divide-by-two correctly. Designed in 0.13 μm CMOS technology, the ILFD occupies a core area of 0.76 mm2 while drawing 7 mA of current from 2.5 V power supply. 展开更多
关键词 CMOS INJECTION-LOCKED frequency DIVIDER (ILFD) LOCKING Range VCO WIDEBAND
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